


The Beast Inside

by thosewhoslitherinthedark



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Blood and Violence, Breeding, Canonical Character Death, Consensual Sex, Crests (Fire Emblem: Three Houses), Don't Like Don't Read, F/M, Impregnation, Incest, Loss of Virginity, Masturbation, Mating, Mating Cycles/In Heat, Monster sex, Monsterfucking, Rough Sex, Spoilers, huge clit, read the tags
Language: English
Status: Completed
Published: 2019-12-11
Updated: 2019-12-11
Packaged: 2021-03-07 19:28:29
Rating: Explicit
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 1
Words: 1,742
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21757255
Author URL: https://archiveofourown.org/users/thosewhoslitherinthedark/pseuds/thosewhoslitherinthedark
Summary: The Crest of the Beast calls to Marianne, luring her out to the Sealed Forest where Maurice, her ancestor, is waiting for his mate...
Relationships: Marianne von Edmund/Maurice
Comments: 2
Kudos: 27





	The Beast Inside

**Author's Note:**

> There are some spoilers for Marianne's paralogue. While that is supposed to take place in Margrave Edmund's territory, I had this take place in the Sealed Forest so Marianne could be lured out from the monastery.
> 
> You're here for the monsterfucking anyway, am I right?
> 
> Warning: This is a fic about Marianne getting fucked and knocked up by Maurice, who is a) her ancestor and b) a monster. If this isn't your kind of thing or is likely to cause you harm, don't read it. It's unabashedly horny and I make no apologies for it. (fic spoiler) The major character death tag is for Maurice.

Marianne stiffened as she felt the curse twist inside her once again. The cover of night brought with it desire and fear, and she wondered what hideous acts she would feel compelled to perform tonight.

It was her Crest. It had to be. No normal woman had fantasies like hers. Her clit throbbed and she closed her eyes, trying to will the urges away. She staggered over to her dresser, grabbing her key, which she fumbled in the lock as she secured the door and tossed the key into a dusty corner. Hopefully, in her madness, she could avoid doing something she would later regret with this simple act. It had worked thus far, but the ache inside grew with each passing night, calling her into the woods.

Calling her to mate with a Crest Beast, to let it impregnate her with its seed. Maurice had been her ancestor, and his Crest had turned him into a monster. Marianne had suffered no such physical transformation, but each night, she was tormented by sexual urges both unnatural and horrifying. No man would ever want to marry her if they knew that she longed to be fucked by a monster. 

Sometimes, even fighting the beasts was too much. The smell that repulsed her former classmates enticed her, causing her nipples to grow hard and her pussy to gush even as she sliced the monsters open with her sword. She longed to cast healing magic on them instead and offer these poor, misunderstood beasts her compassion and her body. Would they accept her, or simply rend her limb from limb?

It was getting harder to fight the call. She dropped to her knees, crawling across the carpet to where she'd thrown the key. She stopped halfway, leaning against the wall. She needed release, and she needed it now. She pulled her dress down, releasing her ample breasts, and tugged the skirts up to expose her wet pussy to the air. She squeezed a nipple as she found her slit with her right hand, spreading her juices over her larger-than-average clit. It stood erect like a tiny dick and she rubbed it, panting and groaning like an animal as she imagined being impaled on a monster's cock. She bit her lip as she came, drawing blood, but the release offered her only a moment's peace. Shame flooded her as her clit continued to throb, still erect and wanting. It wasn't enough any more. She needed him. She needed Maurice.

Maurice was close. She knew he dwelled in the Sealed Forest, and it was his call she heard, his scent that reacted with her. Despite being her ancestor, Marianne knew he was the monster she was being drawn to. The forbidden nature of fucking a monster who also happened to be a relative was an irresistible call, and she was ready to dash her boat against the rocks and end years of repression to have what she wanted. Just the thought of it almost made her cum again. No, tonight, touching herself wasn't going to cut it. She had to find him and end this once and for all.

She made herself presentable before pulling a thick fur coat off the back of her chair and throwing it around her shoulders. She reached down behind the dresser and found the key. This had to end, and the only way she could lift this curse was to fulfill it. Let Maurice shoot his seed inside her. She was human. It might not even take, now that they were different species. Or maybe they would, and she'd give birth to monster babies, nursing them in secret and keeping them hidden from the Professor and the Church. Or, perhaps the magical transformation rendered Maurice no less human after all, and his seed would give her a precious human child.

She had no choice. She'd come too far to doubt herself now. Maurice had waited for her long enough, and she could smell his need on the wind as she stepped out into the monastery grounds. It was late, and most of the officers were asleep. Nobody ever had to know what she was about to do.

She lit a torch as she entered the Sealed Forest. A thick fog covered the area, shrouding her from the monsters, but she could sense eyes on her, watching her movements and trying to discern if she was a threat. She caught a glimpse of red monster eyes and looked away, following the scent that led her deeper into the trees.

A huge roar made her drop her torch and stagger backwards. She fell in the mud, losing her furs and tearing her dress. A monster emerged from the fog, bigger than any Crest beast she'd ever laid eyes upon.

"Maurice, is that you?" Marianne whispered. The beast seemed to calm, sniffing the air. A huge tongue darted out from its mouth, licking the mud from her face. The beast stepped forward, and Marianne noticed a long dick starting to emerge from a sheath on the underside of its body. It looked much like the times she'd seen a horse with an erection, and she knew something like that would surely hurt to take inside her.

Still, she wanted it. She lifted her skirts and the beast descended on her, tearing off her dress with its claws. She lay in the remnants as the creature loomed over her, its colossal cock drooling with want. Marianne reached up and grasped it with both hands.

"It's all right, Maurice. I've come to free us both from this curse." She spread her legs, glad she was so aroused as she took the monster's cock and rubbed it along her slit, coating it in her slick. She guided the head to her hole, gritting her teeth as she stuffed the length inside herself, fucking herself with Maurice's cock.

"We mustn't," Maurice growled, and Marianne's eyes widened in shock as she realized this monster was fully aware of the situation. "I could harm you."

"I'm a healer," Marianne whispered. "I know you need to mate, Maurice. I have the Crest of the Beast. I can feel your need. I can smell it. It resonates with my own."

"I am no longer human… I do not know what hideous creatures I might plant inside you. If those at the monastery knew of this… they may harm you in the Goddess' name."

"That is my burden to bear. Please…" Marianne gasped in a combination of pleasure and pain as Maurice howled and thrust into her, tearing her and taking her virginity. She bit back her tears, resting her hand over her womb and casting a healing spell to stem any internal bleeding.

"I cannot hold back… It has been too long…" Maurice growled. It gripped one huge breast in its claws and lashed the nipple with its tongue, causing Marianne to cry out. The beast made disgusting rutting noises as it fucked into her, animalistic grunts and gasps leaving its mouth as she sobbed with shame and from overstimulation. It let go of her breast and proceeded to lick her throbbing clit, causing her to scream as she came. She clamped down on the huge monster shaft inside her, knowing she was every bit the hideous beast her father had warned her she'd be. She loved this. She wanted this. The stretch of Maurice's cock was almost too much to bear, but she'd been made for this the second she'd been born with this Crest.

Perhaps it wasn't a curse, but a blessing. She wanted to do this again. She wanted to be Maurice's bride, carry his babies, and damn what the Church or anyone else had to say about it. Rumor had it Rhea was a dragon, and Byleth related to her in a sense, yet the two seemed to be intimate. Was what she was doing here any worse? Yet they'd judge her and forgive themselves, as Rhea always seemed to do.

With a roar loud enough to make her ears ring, Maurice came inside her, pumping warm semen into her as his beastly orgasm went on and on. The monster pulled out, and Marianne could feel his cum dribbling out of her stretched hole. If it was possible, she'd be pregnant for sure. The thought of it excited her. She'd always wanted to be a mother, and now this child was hers. No lord could steal her baby from her and treat it like she'd been treated.

"Marianne!" Marianne stiffened and froze as she heard Byleth's faraway shout.

"They come," Maurice growled. "Your classmates."

"You must run," Marianne whispered.

"I am tired, Marianne. I have lived in this form for so long. I think, now that I have mated, I wish for peace at last. I want you to pretend I attacked you and let your professor kill me."

"Maurice, you can't leave me!" Marianne sobbed.

"I'll give you my sword. Protect our child… our legacy. Please, my precious Marianne. Child of my children. You've done so well." Maurice backed away and let out a huge roar.

"We're coming to save you!" Byleth yelled, darting through the trees. He jumped into the air, and lopped Maurice's head clear of his body with one swing of the Sword of the Creator. Marianne covered herself with her tattered dress and muddy furs, spreading the mud and blood over her body to make it look like the minor scratches she'd suffered were the result of a monster attack. None could know about her baby. It was hers. Nobody was going to take it from her.

"You're safe, now," Byleth said. Seteth, Flayn, and other classmates emerged from the trees and helped Marianne to her feet. She sobbed as she looked back at Maurice, her beautiful beast slain by a church and former classmates she was starting to resent. Perhaps Edelgard hadn't been so wrong after all. She pulled herself free of Flayn's steadying arm and walked over to Maurice's body, pulling the sacred sword Blutgang from his open belly and covering herself in the beast's blood in the process.

These people she'd served alongside at the Officers' Academy… they were the real monsters here. Not the child stirring inside her. That was her salvation, her destiny. She gripped the hilt of Blutgang tightly and resolved to kill anyone who tried to harm her baby… even if those people were her friends.


End file.
